<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Auth
 * @subpackage Zend_Auth_Adapter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: DbTable.php 18951 2009-11-12 16:26:19Z alexander $
 */


/**
 * @see Zend_Auth_Adapter_Interface
 */
require_once 'Zend/Auth/Adapter/Interface.php';

/**
 * @see Zend_Db_Adapter_Abstract
 */
require_once 'Zend/Db/Adapter/Abstract.php';

/**
 * @see Zend_Auth_Result
 */
require_once 'Zend/Auth/Result.php';


/**
 * @category   Zend
 * @package    Zend_Auth
 * @subpackage Zend_Auth_Adapter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Auth_Adapter_DbTable implements Zend_Auth_Adapter_Interface
{

	/**
	 * Database Connection
	 *
	 * @var Zend_Db_Adapter_Abstract
	 */
	protected $_zendDb = null;

	/**
	 * @var Zend_Db_Select
	 */
	protected $_dbSelect = null;

	/**
	 * $_tableName - the table name to check
	 *
	 * @var string
	 */
	protected $_tableName = null;

	/**
	 * $_identityColumn - the column to use as the identity
	 *
	 * @var string
	 */
	protected $_identityColumn = null;

	/**
	 * $_credentialColumns - columns to be used as the credentials
	 *
	 * @var string
	 */
	protected $_credentialColumn = null;

	/**
	 * $_identity - Identity value
	 *
	 * @var string
	 */
	protected $_identity = null;

	/**
	 * $_credential - Credential values
	 *
	 * @var string
	 */
	protected $_credential = null;

	/**
	 * $_credentialTreatment - Treatment applied to the credential, such as MD5() or PASSWORD()
	 *
	 * @var string
	 */
	protected $_credentialTreatment = null;

	/**
	 * $_authenticateResultInfo
	 *
	 * @var array
	 */
	protected $_authenticateResultInfo = null;

	/**
	 * $_resultRow - Results of database authentication query
	 *
	 * @var array
	 */
	protected $_resultRow = null;

	/**
	 * __construct() - Sets configuration options
	 *
	 * @param  Zend_Db_Adapter_Abstract $zendDb
	 * @param  string                   $tableName
	 * @param  string                   $identityColumn
	 * @param  string                   $credentialColumn
	 * @param  string                   $credentialTreatment
	 * @return void
	 */
	public function __construct(Zend_Db_Adapter_Abstract $zendDb, $tableName = null, $identityColumn = null,
	$credentialColumn = null, $credentialTreatment = null)
	{
		$this->_zendDb = $zendDb;

		if (null !== $tableName) {
			$this->setTableName($tableName);
		}

		if (null !== $identityColumn) {
			$this->setIdentityColumn($identityColumn);
		}

		if (null !== $credentialColumn) {
			$this->setCredentialColumn($credentialColumn);
		}

		if (null !== $credentialTreatment) {
			$this->setCredentialTreatment($credentialTreatment);
		}
	}

	/**
	 * setTableName() - set the table name to be used in the select query
	 *
	 * @param  string $tableName
	 * @return Zend_Auth_Adapter_DbTable Provides a fluent interface
	 */
	public function setTableName($tableName)
	{
		$this->_tableName = $tableName;
		return $this;
	}

	/**
	 * setIdentityColumn() - set the column name to be used as the identity column
	 *
	 * @param  string $identityColumn
	 * @return Zend_Auth_Adapter_DbTable Provides a fluent interface
	 */
	public function setIdentityColumn($identityColumn)
	{
		$this->_identityColumn = $identityColumn;
		return $this;
	}

	/**
	 * setCredentialColumn() - set the column name to be used as the credential column
	 *
	 * @param  string $credentialColumn
	 * @return Zend_Auth_Adapter_DbTable Provides a fluent interface
	 */
	public function setCredentialColumn($credentialColumn)
	{
		$this->_credentialColumn = $credentialColumn;
		return $this;
	}

	/**
	 * setCredentialTreatment() - allows the developer to pass a parameterized string that is
	 * used to transform or treat the input credential data
	 *
	 * In many cases, passwords and other sensitive data are encrypted, hashed, encoded,
	 * obscured, or otherwise treated through some function or algorithm. By specifying a
	 * parameterized treatment string with this method, a developer may apply arbitrary SQL
	 * upon input credential data.
	 *
	 * Examples:
	 *
	 *  'PASSWORD(?)'
	 *  'MD5(?)'
	 *
	 * @param  string $treatment
	 * @return Zend_Auth_Adapter_DbTable Provides a fluent interface
	 */
	public function setCredentialTreatment($treatment)
	{
		$this->_credentialTreatment = $treatment;
		return $this;
	}

	/**
	 * setIdentity() - set the value to be used as the identity
	 *
	 * @param  string $value
	 * @return Zend_Auth_Adapter_DbTable Provides a fluent interface
	 */
	public function setIdentity($value)
	{
		$this->_identity = $value;
		return $this;
	}

	/**
	 * setCredential() - set the credential value to be used, optionally can specify a treatment
	 * to be used, should be supplied in parameterized form, such as 'MD5(?)' or 'PASSWORD(?)'
	 *
	 * @param  string $credential
	 * @return Zend_Auth_Adapter_DbTable Provides a fluent interface
	 */
	public function setCredential($credential)
	{
		$this->_credential = $credential;
		return $this;
	}

	/**
	 * getDbSelect() - Return the preauthentication Db Select object for userland select query modification
	 *
	 * @return Zend_Db_Select
	 */
	public function getDbSelect()
	{
		if ($this->_dbSelect == null) {
			$this->_dbSelect = $this->_zendDb->select();
		}

		return $this->_dbSelect;
	}

	/**
	 * getResultRowObject() - Returns the result row as a stdClass object
	 *
	 * @param  string|array $returnColumns
	 * @param  string|array $omitColumns
	 * @return stdClass|boolean
	 */
	public function getResultRowObject($returnColumns = null, $omitColumns = null)
	{
		if (!$this->_resultRow) {
			return false;
		}

		$returnObject = new stdClass();

		if (null !== $returnColumns) {

			$availableColumns = array_keys($this->_resultRow);
			foreach ( (array) $returnColumns as $returnColumn) {
				if (in_array($returnColumn, $availableColumns)) {
					$returnObject->{$returnColumn} = $this->_resultRow[$returnColumn];
				}
			}
			return $returnObject;

		} elseif (null !== $omitColumns) {

			$omitColumns = (array) $omitColumns;
			foreach ($this->_resultRow as $resultColumn => $resultValue) {
				if (!in_array($resultColumn, $omitColumns)) {
					$returnObject->{$resultColumn} = $resultValue;
				}
			}
			return $returnObject;

		} else {

			foreach ($this->_resultRow as $resultColumn => $resultValue) {
				$returnObject->{$resultColumn} = $resultValue;
			}
			return $returnObject;

		}
	}

	/**
	 * authenticate() - defined by Zend_Auth_Adapter_Interface.  This method is called to
	 * attempt an authenication.  Previous to this call, this adapter would have already
	 * been configured with all nessissary information to successfully connect to a database
	 * table and attempt to find a record matching the provided identity.
	 *
	 * @throws Zend_Auth_Adapter_Exception if answering the authentication query is impossible
	 * @return Zend_Auth_Result
	 */
	public function authenticate()
	{
		$this->_authenticateSetup();
		$dbSelect = $this->_authenticateCreateSelect();
		$resultIdentities = $this->_authenticateQuerySelect($dbSelect);

		if ( ($authResult = $this->_authenticateValidateResultset($resultIdentities)) instanceof Zend_Auth_Result) {
			return $authResult;
		}

		$authResult = $this->_authenticateValidateResult(array_shift($resultIdentities));
		return $authResult;
	}

	/**
	 * _authenticateSetup() - This method abstracts the steps involved with making sure
	 * that this adapter was indeed setup properly with all required peices of information.
	 *
	 * @throws Zend_Auth_Adapter_Exception - in the event that setup was not done properly
	 * @return true
	 */
	protected function _authenticateSetup()
	{
		$exception = null;

		if ($this->_tableName == '') {
			$exception = 'A table must be supplied for the Zend_Auth_Adapter_DbTable authentication adapter.';
		} elseif ($this->_identityColumn == '') {
			$exception = 'An identity column must be supplied for the Zend_Auth_Adapter_DbTable authentication adapter.';
		} elseif ($this->_credentialColumn == '') {
			$exception = 'A credential column must be supplied for the Zend_Auth_Adapter_DbTable authentication adapter.';
		} elseif ($this->_identity == '') {
			$exception = 'A value for the identity was not provided prior to authentication with Zend_Auth_Adapter_DbTable.';
		} elseif ($this->_credential === null) {
			$exception = 'A credential value was not provided prior to authentication with Zend_Auth_Adapter_DbTable.';
		}

		if (null !== $exception) {
			/**
			 * @see Zend_Auth_Adapter_Exception
			 */
			require_once 'Zend/Auth/Adapter/Exception.php';
			throw new Zend_Auth_Adapter_Exception($exception);
		}

		$this->_authenticateResultInfo = array(
            'code'     => Zend_Auth_Result::FAILURE,
            'identity' => $this->_identity,
            'messages' => array()
		);

		return true;
	}

	/**
	 * _authenticateCreateSelect() - This method creates a Zend_Db_Select object that
	 * is completely configured to be queried against the database.
	 *
	 * @return Zend_Db_Select
	 */
	protected function _authenticateCreateSelect()
	{
		// build credential expression
		if (empty($this->_credentialTreatment) || (strpos($this->_credentialTreatment, '?') === false)) {
			$this->_credentialTreatment = '?';
		}

		$credentialExpression = new Zend_Db_Expr(
            '(CASE WHEN ' .
		$this->_zendDb->quoteInto(
		$this->_zendDb->quoteIdentifier($this->_credentialColumn, true)
		. ' = ' . $this->_credentialTreatment, $this->_credential
		)
		. ' THEN 1 ELSE 0 END) AS '
		. $this->_zendDb->quoteIdentifier(
		$this->_zendDb->foldCase('zend_auth_credential_match')
		)
		);

		// get select
		$dbSelect = clone $this->getDbSelect();
		$dbSelect->from($this->_tableName, array('*', $credentialExpression))
		->where($this->_zendDb->quoteIdentifier($this->_identityColumn, true) . ' = ?', $this->_identity);

		return $dbSelect;
	}

	/**
	 * _authenticateQuerySelect() - This method accepts a Zend_Db_Select object and
	 * performs a query against the database with that object.
	 *
	 * @param Zend_Db_Select $dbSelect
	 * @throws Zend_Auth_Adapter_Exception - when a invalid select object is encoutered
	 * @return array
	 */
	protected function _authenticateQuerySelect(Zend_Db_Select $dbSelect)
	{
		try {
			if ($this->_zendDb->getFetchMode() != Zend_DB::FETCH_ASSOC) {
				$origDbFetchMode = $this->_zendDb->getFetchMode();
				$this->_zendDb->setFetchMode(Zend_DB::FETCH_ASSOC);
			}
			$resultIdentities = $this->_zendDb->fetchAll($dbSelect->__toString());
			if (isset($origDbFetchMode)) {
				$this->_zendDb->setFetchMode($origDbFetchMode);
				unset($origDbFetchMode);
			}
		} catch (Exception $e) {
			/**
			 * @see Zend_Auth_Adapter_Exception
			 */
			require_once 'Zend/Auth/Adapter/Exception.php';
			throw new Zend_Auth_Adapter_Exception('The supplied parameters to Zend_Auth_Adapter_DbTable failed to '
			. 'produce a valid sql statement, please check table and column names '
			. 'for validity.');
		}
		return $resultIdentities;
	}

	/**
	 * _authenticateValidateResultSet() - This method attempts to make certian that only one
	 * record was returned in the result set
	 *
	 * @param array $resultIdentities
	 * @return true|Zend_Auth_Result
	 */
	protected function _authenticateValidateResultSet(array $resultIdentities)
	{

		if (count($resultIdentities) < 1) {
			$this->_authenticateResultInfo['code'] = Zend_Auth_Result::FAILURE_IDENTITY_NOT_FOUND;
			$this->_authenticateResultInfo['messages'][] = 'A record with the supplied identity could not be found.';
			return $this->_authenticateCreateAuthResult();
		} elseif (count($resultIdentities) > 1) {
			$this->_authenticateResultInfo['code'] = Zend_Auth_Result::FAILURE_IDENTITY_AMBIGUOUS;
			$this->_authenticateResultInfo['messages'][] = 'More than one record matches the supplied identity.';
			return $this->_authenticateCreateAuthResult();
		}

		return true;
	}

	/**
	 * _authenticateValidateResult() - This method attempts to validate that the record in the
	 * result set is indeed a record that matched the identity provided to this adapter.
	 *
	 * @param array $resultIdentity
	 * @return Zend_Auth_Result
	 */
	protected function _authenticateValidateResult($resultIdentity)
	{
		$zendAuthCredentialMatchColumn = $this->_zendDb->foldCase('zend_auth_credential_match');

		if ($resultIdentity[$zendAuthCredentialMatchColumn] != '1') {
			$this->_authenticateResultInfo['code'] = Zend_Auth_Result::FAILURE_CREDENTIAL_INVALID;
			$this->_authenticateResultInfo['messages'][] = 'Supplied credential is invalid.';
			return $this->_authenticateCreateAuthResult();
		}

		unset($resultIdentity[$zendAuthCredentialMatchColumn]);
		$this->_resultRow = $resultIdentity;

		$this->_authenticateResultInfo['code'] = Zend_Auth_Result::SUCCESS;
		$this->_authenticateResultInfo['messages'][] = 'Authentication successful.';
		return $this->_authenticateCreateAuthResult();
	}

	/**
	 * _authenticateCreateAuthResult() - This method creates a Zend_Auth_Result object
	 * from the information that has been collected during the authenticate() attempt.
	 *
	 * @return Zend_Auth_Result
	 */
	protected function _authenticateCreateAuthResult()
	{
		return new Zend_Auth_Result(
		$this->_authenticateResultInfo['code'],
		$this->_authenticateResultInfo['identity'],
		$this->_authenticateResultInfo['messages']
		);
	}

}
